This GeoGebra applet enables you to select the number of sides for the polygon, ranging from three (3) to twelve (12), by adjusting the slider.

For each polygon, use the line segment tool to decompose it into triangles. Then, determine the sum of the interior angles of each polygon using your prior knowledge of the sum of the interior angles of a triangle. Record each sum in the table below the applet.[br][br]Finally, determine the [b][i]formula for the [color=#1155cc]sum of interior angles[/color] of an [color=#1155cc]n-sided polygon.[/color] [/i][/b]

Using the data from the table above, determine the formula for the sum of interior angles of an n-sided polygon. [br][br]Use the GeoGebra note for solutions and other scratchwork.